> SLUB gave me a NULL pointer dereference in slab_alloc(), in the> slab_lock(page) of its "Current cpuslab is acceptable" block: cpu> 1 had been looking at cpu_slab[2], which then went NULL beneath it.> Since new_slab() may reenable interrupts and sleep (when __GFP_WAIT),> we may get rescheduled on a different cpu: so need to reevaluate it.